I have a leftover laptop drive and sata - usb adapter. I'd like to make it bootable and 'portable'. Would it be able to recognize host machine's network card for instance? For the sake of experiment I installed latest distro of Suse (curiosity). All went well except when it booted it would not recognize my wireless network. I shut down the laptop I had it plugged into, un-plugged it and tried to boot the laptop. Of course grub was hosed ( fixed it with no problems ). The interesting thing was when I booted from Ubuntu Live CD to fix grub, my wireless network was recognized just fine. When I tried to plug in the usb drive, rebooted and hoped to boot into the usb drive - no joy.

Any suggestions on where to start with making such an autonomous Ubuntu set up?

4/11/13 Figured it out.
Took my desktop and unplugged all the hardrives. Booted from live dvd. Plugged in the laptop drive through usb connector. Run installer and got a 'normal' install on the hard drive. Note to self: get eSATA case and cable for the drive, booting from the drive via usb a bit too slow.